Recording apparatus for use with aviation ground trainers



Oct. 13, 1,942. r c, 'w.' MULLER 2,298,305 RECORDING APPARATUS RoR USEwITVH AVIATION *GROUNDy TRAINERs I 4 Sheets-Sheet l VFiled Dec. 8, 194;

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RECORDING APPARATUS ROR USR wITH AVIATION GROUND TRAINERS Filed Dec. 8,1941. Sheets--Sheeizl 2 AffroRNs/ Oct. 13, l1942),. l c. w. MULLERRECORDING 'TAPARATUS FOR USE WITH Av'IA'rIon'GRoUND -TMINERS Filed Des.8, 1941 4 Sheets-Sheet 3` M, .a M. W

oct. 13, 1942.

` C. W. MULLER RECORDING APPARATUS FOR USE WITH AVIATION GROUND TRAINERSFiled Dec. 8, 1941 Patented Oct. 13, 1942 UNITED STATE REQRDINGAPPARATUS FOB Usl VITII AVIATION GEO om w. Mauer-,oem omo ApplicationDecember s, 1941, semi N. 422,09:

zo claims. (ci. .t- 12) (Granted under the act of March 3,. 1883, asIntended April 39, 19283 -37 0. G. `'1257) 'I'he invention describedherein may be manufactured and used by or fory Government for gov-`ermental purposes, without the payment to me of any royalty thereon.

This invention relates to auxiliary apparatus for use in conjunctionwith aviation ground training apparatus such as the well-known Linktrainer, whereby ground instruction of students in problems involvingthe navigation of aircraft from moving bases.. such as aircraft'carriers, wherein the aircraft is assumed -to y from the base tointercept a moving target or to proceed on a patrol mission and thenreturn to the base, may be accomplished in a simple manner and apermanent record made of all factors involved in a particular problem.

In copending application Serial No. 320,880, filed February 26, 1940,for "Interception trainer, in the names of Carl J. Crane, George V.Holloman, Carl W. Muller, and Raymond K.

Stout, one partial solution of the-problem 0f proing visually determinedby the instructor; andA this application further disclosed the use of amoving transparent belt or belts to cause a displacement of therespectiverecorders to simulate the drift effects of winds or tides.'This appaf ratus, while satisfactory in certain respects, did notprovide for simulating .operation from a mov- In accordance with thepresent invention, the conventional course recorder such as employedwith the Link trainer land directionally c ontrolled thereby, issupported for movement onla supporting surface having a record charttheref on, the surface itself being secured to a movable carriagesimilar to thefwind-simulating device disclosed in the aforementionedcopending applisimulating carriage traveling ina known directin andvelocity traces the windfactors on the associated chart placed on thesupporting table.

In order to simulate operation from a moving base, a second carriagesimilar to the wind-simulating 'carriage is provided, which has securedthereon a suitable chart-supporting surface, and

the carriage is set in motion over the supporting table for movementrelative to a chart placed thereon, in af direction and at a velocitycorrespending to 'the assumed direction and proportional to the assumedvelocity of the moving base, representing, for example, anaircraftcarrier. A tracer arm carried by the trainer recorder is adapted totrace the course of the assumed flight ing base-i. e., after thesimulated interception of the aircraft relative to the moving baseon thewas accomplished, no provision for simulating the return of the aircraftto s. moving base was provided-and further it was not possible to make arecord of all of the factors involved in the prob lem, and hence therewas no way of checking the solution of the problem to rectify faultynavigation on the part of the student.

The development by Carl J. Crane of a very simple wind-simulating devicesuch as disclosed and claimed in his copending'application Serial No,334,002, entitled Apparatus for simulating wind eiiectsfforms the basisofthe present invention, which employs a plurality of such devices in amanner that a complete solution and record of problems involvingoperation from moving bases may be accomplished. It is ot course to beunderstood that the constructioner se .ofsuch devices as" disclosed inAeither 'ofthe aforementioned copending applications forma no part ofthe present invention. e-

chart carried by the second carriagel and, since the second carriagetraces its our course on an associated stationary chart. arecord ofall'of the factors necessary to criticize the solution of Aa 40 problemis provided. When the recording marker problems,Y 'a-third carriagehavin! a chart-supporting surface is provided for movement over thesupporting table relative to an associated stationary chart upon whichthe third carriage traces course of the target object representedthere..

by, such as an enemy ship. A second tracing arm carried by the trainercourse recorder is provided for tracing the relative motion between theassumed flight of an aircraft relative to the simulated target object ona chart carried on the supporting surface of the third carriage. If thechart carried by the third carriage is markedpreferably at a pointdirectly over the marker 'carried by the third carriage, employed fortracing the course of the target object-and the marked point and themarker are placed over a selected starting point on the record chart onthe table on which the third carriage marker records, then if theinterception problem is correctly solved, the marker on the secondtracer arm should pass through the said marked point on the chartcarried` by the said third carriage, and a complete trace of theinterception problem is left on the chart carried by the third carriage.

It is therefore the principal object of the invention to provide, inconjunction with an aviation ground trainer for simulating the ilight ofvan aircraft and a course recorder therefor, movable means forsimulatingA the course of a moving base such as an aircraft carrier, orof a target object, relative to the assumed Hight course of an aircraftrepresented by said trainer, and recording means carried by the courserecorder for tracing the relative movement between the moving base orthe target object and the assumed course of the aircraft, on a recordsheet carried by the movable means.

It is another object of the invention to provide, in conjunction withanaviation ground trainer for simulating the flight of an aircraft and arecorder therefor, means for movingsaid recorder over a supportingsurface in a direction and at a velocity corresponding to the directionand velocity of a wind assumed to be acting on said aircraft, meansmovable relative to the support-r ing surface in a manner representing:a moving base from which said aircraft is assumed to depart and return,and tracing means carried by the course recorder for tracing the courseof the assumed flight of the aircraft relative to the said moving baseupon a chart carried by said lastnamed movable means.

It is a further object of the invention to provide means wherebythesimulated ight course of an aircraft as represented by the controlledmovement of a ground trainer course recorder may be correlated to themovement of a chart carried by a means movable pver a supporting surfacein a manner simulating thecourse of a target object such that a tracingmeans carried by the course recorder is 'adapted to trace the simulatedflight course of the said aircraft relative to the simulated course ofthe target object, on the record sheet. ....w... .-v.

Other objects of the invention will become apparent by reference to thefollowing detailed description and to the appended drawings in which: i

Fig. 1 is an assembly view illustrating the arrangement of the componentelements of vthe invention for the solution of navigation problemsinvolving a moving base;

Fig. 2 is a side elevation view illustrating the details of thewind-simulating carriage and the trainer course indicator illustrated inFig. 1;

Fig. 3 is a top plan view of the recording apparatus illustrated in Fig.1;

Fig. 4 is an assembly view similar to Fig. 1 1llustrating additionalapparatus employed for the` solution of interception problems; and

Fig. 5 is a top plan view of the apparatus illustrated in Fig. 4.

Referring now to Fig. 1, the reference numeral l generally indicates anaviation ground trainer of the character illustrated and described inUnited States Patents Nos. 1,825,462 and 2,099,857 granted to Edwin A.Link, Jr., and comi prising a fuselage serving as a cockpit enclosurefor the student receiving the instruction, which is tiltably androtatably mounted on a base 2 and adapted, through means controlled bythe student, to vsimulate the various attitudes of an aircraft duringflight. 4The,trainer is provided.

with `a self-synchronous transmitter unit S electrically connected bymeans ofconductors in the conduit 3 to a corresponding self-synchronousreceiver Si which is mounted on the course indicator 5, which also is ofwell-known construction, and illustrated and described in United StatesPatent No. 2,179,663 granted to Edwin A. Link, Jr. As the trainer I isrotated in azimuth about the basel 2, the self-synchronous transmitter Scauses a corresponding angular rotationof the rotor in the receiverlunit Si which controls the azimuth heading of the recorder 5 to at alltimes correspondl to the instant heading of the trainer I.

The recorder 5, as seen in Figs. 1 and 2, is provided with a frame orbase 6 which serves as a.

by means of small, geared-head, synchronousmotors 9 which are suppliedwithl current of a selected frequency'such that the recorder 5 will bepropelled in translation relative to the trainer table 4 at a velocitycorresponding in some predetermined scale to the assumed velocity inflight of an aircraft represented by the trainer I. The recorder 5is-also provided with a downwardly de'pending steerable spindle I0 whichserves as a mounting for a supporting roller I2, which may be inked byany suitable means (not shown) to ceiver Si is thus adapted to controlthe heading of invention.

the course indicator l so that the same always corresponds to theinstant heading of the trainer I. Th above-described ground trainer andrecorder being well known in the art, the construc- 'rim conventionalrecorder s is provided with a vertically extending U-shaped frame Ilwhich serves as a mounting for a pivot I5 to which is secureda longtracer arm It made, for example, of light aluminum tubing and providedat its outer end with a holder element I'I in which is secured asuitable marker Il which may be, for example, a pencil or inking penwhich is adapted .to trace a'record as will be hereinafter more eralconstruction as disclosed in the aforementioned co-pending applicationof Carl J. Crane, Serial No. 334,002 and the construction of which Iperse also forms no part of the present invention, but in order to give aclear understanding of the invention a description of the wind simulatorwill now be given. The wind-simulating carriage generally indicated bythe reference numeral 25, as seen in'detail in Figs. 1 and 2,-is

l provided with a table portion 26 which serves as a support for thecourse recorderA which is adapted to trace a record on the chart C1placed on the table 26. The table 26 of the wind-simulating carriage 25serves as a main frame which is provided with downwardlydependingbearing bosses 21 which, as shown, -are four in number and each adaptedto rotatably journal a4 steerable spindle A28 which serves as mountingmeans for rollers 36 lsecured to the lower end thereof,

Operation n Prior to placing trainer I -into operation,l the instructorsets the direction of the assumed wind in the Wind-simulating carriagebymeans of f rotating dial136 relative to pointer 31 in the manner asvpreviously noted and selects the simulated velocity of the wind byproper selection of the two of the rollers being adapted to bepropelledby means of small synchronous motors 32 which may be suppliedwith alternating current of a selected frequency such that the carriage25 will be propelled in translation ov'er the chart Cz-on the trainertable 4 at a`velocity proportional in .a predetermined scale to thevelocity of an assumed Wind. Each of the spindles 28 has mounted thereona pulley/ 34, which pulleys are interconnected by means of a cable 35which serves to transmit rotation from `one spindle to the other. ametal dial '36 which on its upper surface is provided with suitableazimuth indicia, and the dial 36 cooperates with a pointer 31 xed to theframe 26, the pointer also having secured thereto a friction stop 38whereby the dial 36 maybe locked in any desired position. By orientatingthe carriage yframe and table 26 such that a selected axis thereofcoincides, for'example, with a north-south line, the dial 36 may berotated,

and through the pulleys 34 and cable 35 rotatel all of the spindles 28so that the respective rollers v3II have anA azimuthr headingcorresponding to the heading indicated on the scale 36 relative to anorth-south line. VIf then the motors 32.

are energized, the wind-simulating carriage 25 will be propelled intranslation over the -surface of a chart C2 supported on the table 4with a velocity and heading corresponding in a predetermined scale tothe velocity and heading of an assumed wind. The wind-simulatingcarriage One of the spindles is provided with frequency of supply formotors 32, or'by using a gear reduction having the proper value sothatwhen motors 32 are energized the wind-,simulating carriage 25 willbe propelled over the surfacev -of chart C2 in a direction correspondingto the direction of the assumed wind and having a velocity proportionalto the velocity of the assumed wind. The marker 42 Will then trace thecourse of the assumed wind on the chart C2, andv this trace will alsorepresent the wind vector,

since the velocity of the carriage 25 is known, At any time during theconduct of ythe problem thev instructor may change the Wind direction atwill. When the trainer I is td be placed in operation, the frame 6Y ofthe course recorder 5 is properly orientated-With respect to anorth-south line, as is customary in .the art, and upon energizingmotors 9 from a suitable source of alterhating current the courserecorder 5 willv be propelled over the surface -ofchart C1 carried uponthe Wind-simulating'carriage 25 at `a velocity corresponding in apredetermined scale to the veloc- Y ity of flight ofan aircraftrepresented bythe table 26 has a bracket 39 secured to the undersiderthereof which serves as a pivotable support for a tracer arm 40,the latter having a suitable holder 4I secured to its outer end, whichserves to retain a suitable marker 42 which is adapted to tracethecourse of the assumed wind on the chart C2. By changing the frequency ofthe alternating current supplied to `motors 32, the velocity of theywind-simulating carriage may be changed at will; or by employingdifferent gear` ratiosin the motors, the various desired simulated windspeeds may be obtained.

In order to provide apparatus for the solution of problems involvingoperation from a moving base, there is provided, as vseen in Fig. -1,asecond carriage 25a. identical in construction with thewind-sirnulating carriage 25, previously de'- scribed, which may bepropelled over the surface of a chart C3 supported on table 4', in adirection corresponding to the simulated heading ofthe moving baserepresenting, for example, an airtrainer I,-and the heading of thecourse recorder 5 will be directionally controlled by the trainerin themanner previously noted.

After the trainer I is placed in operation, the

Wind-simulating carriage 25 will bodily displace the course recorder 5in a direction correspond-F ing to the direction of thel assumed windand with a velocity proportional to the velocity of the assumed wind(for example, as illustrated in Fig..

3). yThe student in the trainer, knowing -the velocity and direction ofthe assumed wind, must accordingly change the'trainer heading tocompensate for the efectof drift, depending upon the selected .coursethedrift angle being, for example, illustrated on chart C1 in Fig. 3-and atany time -during the conduct of the problem that the wind direction. orvelocity is changed the student may accordingly note such change in hisnavigation computations. assumed. velocity of ight represented by vthespeed of -the course recorder 5, the student may,

on a suitable map, chart the instant position of the assumedflight ofthe aircraft rrepresented by the trainer, since the assumed ground speedmay be readily calculated by any well-'knownmethod.

craft carrier and having a speed proportional K' in accordance with thescale of chart C3 to the assumed speed of the aircraft carrier. The

Priorto placing the trainer'in operation, the I tables 26 and 44a ofthecarriage 25a are properly orientated with respect to a north-southline; the map Ci also being properlyv orientated upon the table 44a-andthe.marker I8 is placed di- -rectly over a marked point on the chart C4having a known latitude and longitude with respect to positionsindicated by chart C4.- This marked By knowing the.

point, such as X, Fig. 3, indicates the aircraft carrier or other movingbase from which the assuiiied flight of the aircraft is to begin andend. The instructor also selects the heading and velocity of the movingbase by adjusting the heading and determining the speed of the carriage25a in exactly the same manner as previously described with reference tothe wind-simulating carriage 25, so that the motion of the carriage 25asimulates the course of the moving base, and the point X on the chart C4is thus displaced with a velocity proportional to the assumed velocityof the moving base and in a direction corresponding to the assumedcourse of the moving base. The student. knowing the assumed latitude andlongitude of the moving base, may plot the initial position of the sameon his map and also plotthe assumed course of the moving base which, ofcourse, may be changed by the instructor from time to time, the studentbeing informed of such course changes by telephonic communication.`

After the trainer is placed in operation, the

`marker I8 will move relative to the point X on the chart C4 to indicatetheassumed flight course keeping in mind the elapsed time from thebeginning of the assumed flight, and thus may, by dead reckoning orother methods of navigation,

to the course and instant position of the moving base represented bythe'point X on the chart C4; and after the assumed mission of theproblem is carried out, the student may so control'the trainer as tosimulate the return to the moving.

base or aircraft carrier represented by the point X on chart C4, and ifall navigation calculations have been properly solved, at the completionof the problem, the marker I8 should again pass through the point X onchart C4, thus representing a safe return to the aircraft carrier, andat the conclusion of the problem the distance by which the assumedflight of the aircraft failed to intercept the point X may be readilydetermined, and thus whether or not the assumed return iiight was suchthat the aircraft carrier would have been sighted.

The various charts C1, C2, Ca, and C4 serve as permanent records of allthe principal variables employed inthe problem, and the record left onchart C4 is irrefutable evidence as to the correctness of the solutionof the particular navigation problem which the student is required tosolve.

-By thus providing definite records, the solution records ser've as avaluable aid in comparing the :work of o'ne student with the solution ofthe problems by other students so that comparative standards of accuracymay be determined.

In order to provide apparatus for simulatingv interception of enemyaircraft or the like, and also provide for the feature of departing fromand returning to a moving base, the assembly is check his instantposition on the map relative Aillustrated and described with referenceto Figs.

1 to 3 inclusive. similar parts being identified by the same referencenumerals; and'in addition to the apparatus of Fig. 1, there is provideda second carriage 25h identicai'in construction with the carriage 25a ofFig. 1, the marker 42h of which is adapted to trace the course of thetarget object on a chart Cs mounted on table l, the carriage 25h beingpropelled over the chart C5 in a selected direction and at a velocitycorresponding to the heading and proportional to the velocity of theassumed target object, the carriage being operated in the same manner.las the wind-simulating carriage 25 and moving-base-simulating carriage25a of Fig. 1. The second tracer arm Ita, identical in construction withthe tracer arm Il of Fie. 1, is mounted on the pivot I5 carried by thebracket I4 of the course recorder 5. and the marker IIb thereofis.,adapted to trace a record on a chart Cs supported on a table b ofthe -carriage 25h, relative motion between the marker Ib and aselectedpoint (for example, Y in Fig. 5 on the chart Ca) representingthe relative motion between the assumed flightA of the aircraftrepresented by the trainer l and the target object represented by thepoint Y on chart Cs, which is displaced in accordance with the assumedcourse of the target object represented by the carriage 25h. Thesolution of the problem is carried out-in a manner similar to thatpreviously described j problem of returnto the moving base in exactlythe same manner as above described with reference to Figs. 1 to 3inclusive. v-

When initially starting the problem, the instructor places the mark Y onthe chart Cs, and

employed as illustrated in Fig. 4, kin which the apparatus including therecorder 5, wind-simulating carriage 25, and the carriage 25arepresenting the moving base, are identical to those places the marker42h directly oyer a corresponding point on the chart Cs representing theassumed latitude and longitude of the target object at the beginning ofthe problem or when the assumed night ofthe aircraft is supposed tocommence from the carrier to intercept the target object. Then k if thestudent properly solves the interception portion 'of the problem, themarker 18h should pass through the pointl Y showing that theinterception has been properly carried out, the trace of the marker Ilbrelative to the point Y thereafter being of no consequence'. By means ofthe marker 42h a permanent record of the assumed course o f the targetobject is provided, and the trace left by the marker Itb on the chart Csshows whether or not the student has properlyv solved the interceptionproblem under the conditions of the assumed 'wind represented by themovement of the carriage 25. 'I'he portion of the problem relatingto thesimulated departure from and return to the aircraft carrier is recordedon chart C4 in the manner as .above described with reference to Figs. 1to 3 inclusive. Y

' It is of course to be understood that with the apparatus disclosed,problems not involving winds may be readily solved simply by maintainingthe wind-simulating carriage 25 stationary, and as noted above, thevelocity of the wind-simulating carriage 25, moving-base carriage 25a,and targetobject carriage 25h, may beselected as desireddirection-finding aids may be employed with the above-,describedapparatus to, for example, facilitate the assumed return flight of theaircraft represented by the trainer to the carrier represented by pointX on the chart C4 carried by the moving-base-simulating carriage 25a.

While a vpreferred embodiment of theA invention' has been illustratedand described, many changes and variations therein will become apparentto those skilled in the art as falling within the scope of the inventionas defined by the C appended Y claims.

I claim:

1. In aviation ground training apparatus of the character described, arst record chart, a. course recorder directionally controlled by theassociated ground trainer for tracing the simulated air path of theassumed flight of an aircraft' Aon said chart, a first. carriage adaptedto move chart on said second carriage having a'point thereonrepresenting said moving. base, and tracing means carried by said courserecorder and adapted to trace a record on the chart carried by saidsecond carriage representing the course of the assumed flight of saidaircraft relative to the point on said chart representing the movingbase.

2, The structure as claimedl in `claim 1, in which said first and saidsecond carriages are each provided with tracing` means. and a pair ofstationary charts each respectively adapted to cooperate with one ofsaid last-named tracing means whereby the record of the courses of theassumed wind and of the moving base will be obtained.

3. An aviation ground training system for inrecord chart carriedby saidsecond carriage, said `marked point on the last-named chart representingthe assumed'moving base,

4. The structure as claimed in claim 3, in which said first and saidsecond carriages are each provided with tracing means, and a pair ofstationary charts, each respectively adapted toA cooperate with one ofsaid last-named tracing means whereby the course of the assumed wind andof the assumed moving base may be obtained. J e

5."In an aviation ground training system in which a rotatable groundtrainer controlled by a student occupant adapted to directionallycontrol a course recorder which is propelled in translation over areference'surface at a velocity proportional to the assumed velocity ofan aircraft represented Aby the trainer: the combination with saidrecorder of a carriage adapted to be propelled in translation over asupporting surface ina direction andata velocity correspending to thedirection and proportional to the velocity of an assumed moving base`such as an aircraft carrier, a chart carried by said carriage andhaving a marked point thereon representing the said moving base, andrecording means mounted on and movable -with said course ref' corder fortracing the course of the assumed flight of said aircraft representedbythe trainer on said chart relative to the point thereon representingthemoving base.

6.`The structure as claimed in claim 5, inwhich therev is provided amovable means for supporting said course recorder for translatoryVvadapted to physically transport said course restructing students inthe art of navigating an aircraft from and returning to a `moving basecomprising: an aviation ground trainer rotatable in azimuth under thecontrol of the student tional to the velocity of said assumed wind, a

second carriage movable in translation with a velocity proportional tothe velocity of an assumed moving base such as an aircraft carrier andwith a heading corresponding to the assumed heading of said moving/base,and tracing means carried by and movable with said course recorder, saidtracing means being adapted to trace a record of the resultant movementof said course recorder relative to a marked pointv on'a corder in adirection-and at a velocity corresponding to the direction andproportional to the velocity of an assumed wind, a record chart carriedby said movable means upon which said course recorder is adapted totrace a record ofthe air track of the assumed flight of saidaircraft,recording means carried by said movable means, and a stationaryrecord chart upon which said last-named recording means is adapted totrace a record of the course of the assumed wind.

8. The structure as claimed in claim 5, including a chart-supportingsurface upon which said course recorder is movable to record the airtrack ofthe assumed flight of the aircraft represented by said trainer,means for propelling said chartsupporting surface in translation in adirection and at a velocity equivalent to an assumed wind, tracing meanscarried byJ said surface for tracing the course ofthe assumed wind on astationary record chart, and tracing means carried by the carriagerepresenting the moving base,

sai`d last-named' tracing means beingrv adapted -to trace the assumedcourse of the moving base the assmned wind respectively.

trainer and movable over a record chart at a velocity proportional tothe assumed velocity in' night of an aircraft represented by saidtrainer, a carriage movable in translation with a directional headingand velocity corresponding to the heading and proportional to thevelocity ofan assumed target object, a chartv carried by said carriagehaving a marked point thereon representing said target object, andtracing means carried by said course recorder for tracing the assumedcourse of the aircraft represented by the ltrainer on said chartrelative to the said marked point thereon representing the targetobject.

10. The structure as claimed in claim 9, in which there is providedmeans for bodily transsaid second carriage having a marked point thereonrepresenting said assumed moving base, and second tracing means carriedby said course recorder adapted to trace the course of the assumed nightof said aircraft on the record sheet carried by said second carriagerelative to the lsaid marked point thereon representing the asportingsaid trainer course recorder in a direction and at a velocitycorresponding to the direction and proportional to the velocity of anassumed wind. f

11. The structure as claimed in claim 9, including a tracing meanscarried by said movable carriage, and a stationary record chart uponwhich said last-named tracing means is adapted to trace a record of theassumed course of said target object.

12. The structure as claimed in claim 9, including a second movable.carriage movable -in translation with a direction and velocityequivalent to an assumed wind, said second carriage having a supportingsurface with a chart thereon, said course recorder being movable on saidsurface to record the air track of the assumed night of said aircraft onthe last-named chart.

13. The structure as claimed in claim 9, including a second carriagemovable in translation in a direction and at a velocity correspondingtothe direction and proportional to the velocity of an assumed wind, asupporting surface on said. second carriage having a chart thereon andsaid course recorder being movable on said surface and adapted to tracea record of the air track of the assumed night of the aircraftrepresented by'said trainer on the chart carried by said surface, eachof said carriages being provided with recording means adapted tocooperate with respective stationary record charts to trace thereonrecords of sumed target object.

17. The structure as claimed in claim 14, in which there is provided asecond power-propelled carriage having a supporting surface with arecord chart thereon, said surface supporting said course recorder fortranslatory movement thereon. said second carriage being adapted to bepropelled in translation in a direction and at a velocity correspondingto the direction and proportional to the velocity of an assumed wind, a

-third power-propelled carriage adapted to be base such as an aircraftcarrier, a chart carried the course of the target obiect and the courseof i 14. Incombination. a course recorder for tracingonarecordsheetthenightcourseofanss-- Apronortional to the velocity and correspondingin direction to an assumed target object. a record sheet carried by saidcarriage and having a by said third carriage having a marked pointthereon representing said moving base, secondY tracing means carried bysaid course recorder and adapted to trace the course of the assumednight of said aircraft relative to the marked point on the chart carriedby said third carriage representing the assumedmoving base, andindividual tracing means carried by each of said carriages and adaptedto trace the course of each carriage on a respective stationary recordchart associated therewith.

=1B. In an aviation ground. training system. a

grounded trainer rotatable in azimuth under the l control of a studentoccupant thereof. a course recorder directionally controlled by saidtrainer and movable over a supporting surface at a velocity proportionalto the. air speed of an sssumed aircraft represented by said trainer, apair of tracing means carried by said course recorder,

. apair of power-propelled carriages each having s chart thereon. oneofsaid carriages being mov- -tionsltotheveiocityofanassumedmoving basesuch as an aircraft carrier. a marked point on marked point thereonrepresenting said target.A

object. and tracing means carried by said course' recorder adaptedtotracethe pathoftheassumed night of said aircraft represented bythetrainer on said record sheet relative to the marked point thereonrepresenting said target object.

15. The structure as claimg in claim 14, in which there is provided apower-propelled carriage movable in translation in a direction and witha velocity corresponding to the direction and proportional to thevelocity of an assumed wind.

said second carriage providing a supporting surface for supporting saidcourse recorder for translatory movement thereon, a chart carried bysaid second carriage upon which the course recorder isadaptedtotracearecordof airtrackof-the assumed night of said aircraft,and tracing means carried by said second carriage adapted to trace thecourse oftheassumed winden arecord chart.

said one carriage chart representing saidmovingbeaeandoneofsaidtracingmeansbeing adsptedtotraee'theeourse of theassumed night of said aircraft on the last-mentioned 4chart relative tosaid point thereon representing the moving base, the other of saidcarriages being movable in a direction and at a velocity correspondingto the direction and proportional to the velocity of an assumed targetobjects marked point on the chart carried by'said last-named carriagerepresenting the assumed target object, and the other of said tracingmeans being adapted to trace a record on said last-mentioned chartrepresenting the course of the assumed night of said Y aircraft relativeto the marked point representing the target object.

19. 'me structure as claimed m-eisim 1e, in-

cluding means for supporting said course recorder'v -for translator-ymovement thereon, said means the direction and proportional to thevelocity of -an assumed wind. v

pelled in translation to physically transport the 10 courseY recorder ina direction and .atawelocity correspondingto the direction andproportionalv to the velocity of an assumed wind,v and each of saidcarriages being provided with a tracing means adapted to trace thecourse thereof on an associated stationary chart thereby obtaining Yrecords of the respective courses of the assumed moving base, theassumed target object, andthe assumed wind.

CARL W. MULLER,

